- Congenital cerebral vascular malformation with mature venous elements
- Umbrella-like collection of enlarged medullary (white matter) veins (“Medusa head”)
- At angle of ventricle
- Converge on single enlarged collector vein
- Imaging
- CT often normal but may see hyperdense collector vein
- MR
- Hypointense on SWI
- Strong enhancement
- T1 can be normal if small and signal is variable depending on size and flow (eg. flow void may or may not be present)
- T2 tubular flow void present
- FLAIR usually normal but occasionally will see hyperintensity adject which reflects venous congestion/ischemia
- Best imaging is T1 w/ contrast which shows strong enhancement
- Can be mixed with cavernous malformations (mixed vascular malformation) with coexisting cavernous and or capillary malformations occurring 15-20% of the time
- More common asymptomatic
- 0.15% risk of hemorrhage per lesion per year
- Solitary DVAs usually not treated as attempts can lead to venous infarction
- If mixed then treatment depends on the mixed component
- Per CTC it is a “do not touch” lesion. If resected can lead to debilitating venous infarct similar to acute thrombosis of DVA. DVA must be preserved if an adjacent cavernous malformation is resected